Pseudohesperus tripartitus, 2011

Li, Liang & Zhou, Hong-Zhang, 2011, Revision and phylogenetic assessment of the rove beetle genus Pseudohesperus Hayashi, with broad reference to the subtribe Philonthina (Coleoptera: Staphylinidae: Staphylinini), Zoological Journal of the Linnean Society 163 (3), pp. 679-722 : 714-715

PSEUDOHESPERUS TRIPARTITUS LI & ZHOU SP. NOV. ( FIG. 29A–H )

Type material: Holotype: ♂, China: Sichuan: Wolong: Wulitun (31°28′N, 103°36′E), 2220 m asl, 6–9.vi.2004, Yu Xiaodong collected (IZ-CAS); paratypes: 2 ♂♂, 1 ♀, same data as holotype, but 2220–2410 m asl, 21.vi.-9.vii.2004 (IZ-CAS).

Description: Head and pronotum black, shining. Antennae dark brown, with antennomere XI or antennomeres X–XI reddish-brown. Elytra reddish-brown. Scutellum dark brown. Abdomen black, with strongly iridescent lustre. Mandibles, maxillary and labial palpi, and legs reddish-brown.

Body 9.55–10.0 mm long ( HPL: 2.86–2.94 mm). Head of rounded quadrangular shape, 1.22–1.39 mm long, 1.14–1.31 mm wide, slightly narrower than long ( HW: HL = 0.93–1.00). Tempora 0.41–0.49 mm long, almost evenly rounded, sparsely and coarsely punctate; eyes small, slightly prominent, 0.33–0.41 mm long, 0.80–0.83 times as long as tempora. Dorsal surface of head with moderately numerous, large setiferous punctures, becoming sparser toward vertex; vertex largely impunctate. Entire head with distinct and profound microsculpture of transverse waves. Antennae long, antennomere I very long, thickened towards apex, antennomere III much longer than antennomere II, following antennomeres gradually decreasing in length, but all longer than wide, antennomere XI obliquely truncated.

Pronotum slightly narrowed anteriad, 1.47– 1.55 mm long, 1.31–1.47 mm wide, slightly wider than head ( PW: HW = 1.06–1.20), sparsely and finely punctate, punctures separated by three to five times their diameter, narrowly impunctate along midline, disc with distinct and profound microsculpture of oblique lines.

Elytra 1.80–2.04 mm long, 1.96–2.04 mm wide, along sides 1.16–1.33 times as long as pronotum, densely and finely punctate, punctures separated by one to two times their diameter. Scutellum large, triangular, densely and finely punctate, and pubescent.

Abdomen a little narrowed posteriad, widest 1.63– 1.88 mm, densely and finely punctate, punctures separated by two to three times their diameter at base, gradually becoming sparser toward apex; tergites III–V with two basal carinae, elevated area between basal carinae almost impunctate.

Male: Sternite VIII with moderately wide, obtusely triangular medioapical emargination, partly filled by semimembranous extension ( Fig. 29E ). Genital segment with stylus of tergite IX simple, densely setose apically. Sternite IX with asymmetrical basal portion, apex deeply emarginate, without modified rod-like extensions ( Fig. 29D ). Tergite X triangular with medioapical emargination ( Fig. 29F ).

Aedeagus similar to that of P. pedatiformis Li & Zhou sp. nov.; median lobe slightly exceeding paramere, narrowed into subacute apex ( Fig. 29A ); in lateral view, apical portion slightly bent dorsad (parameral side) ( Fig. 29B ); paramere trilobed apically, middle lobe distinctly longer and wider than lateral lobes, face adjacent to median lobe with peg setae arranged along apical portion of paramere ( Fig. 29C ).

Female: Sternite VIII with arcuate apex, lacking medioapical emargination. Genital segment with second gonocoxites moderately long, each with minute stylus bearing two long apical setae ( Fig. 29H ). Tergite X triangular, subtruncated at apex, with two long apical setae ( Fig. 29G ).

Etymology: The specific epithet is derived from the Latin word tripartit- (tripart), and refers to the trilobed paramere of the aedeagus.

Distribution: At present known only from the type locality China (Sichuan).

Remarks: Pseudohesperus tripartitus Li & Zhou sp. nov. is closely related to P. pedatiformis Li & Zhou sp. nov. Pseudohesperus tripartitus Li & Zhou sp. nov. differs from the latter species by distinctly smaller eyes and completely different paramere of aedeagus.

Figures

Figure 29. Pseudohesperus tripartitus sp. nov. A, aedeagus, dorsal (parameral side) view; B, median lobe of aedeagus, lateral view; C, underside of paramere; D, sternite IX of male; E, sternite VIII of male; F, tergite X of male; G, tergite X of female; H, gonocoxites of genital segment of female. Scale bars = 0.5 mm.